Author: Sherry Watkins

New ‘Carbohydrate Food Quality Score’ considers a comprehensive and practical approach, aligning with the Dietary Guidelines for Americans

Peer-Reviewed Publication

THE ALLIANCE FOR POTATO RESEARCH AND EDUCATION (APRE)

April 11, 2022 – The dietary value of carbohydrate foods (CF) has come under increased scrutiny in recent years. While so-called good-carb/bad-carb designations are hotly contested, standardized methods for assessing CF health quality currently do not exist. In a paper recently published in Nutrients, the Quality Carbohydrate Coalition-Scientific Advisory Council (QCC-SAC) proposes a novel, innovative approach to quantifying CF quality: the Carbohydrate Food Quality Score (CFQS). Representing a significant step forward in the evolution of CF analysis, the new CFQS incorporates a food’s fiber-to-carbohydrate and free sugar-to-carbohydrate ratios, as previous metrics have done, in addition to evaluating its sodium, potassium and (as applicable) whole grain content, making the index better reflect the nutritional contribution of the entire CF.

“While long-standing evidence clearly establishes that carbohydrate-containing foods are essential to building healthy dietary patterns, people need better tools to identify higher quality choices that can be balanced in a healthy dietary pattern,” said Joanne Slavin, PhD, RD, University of Minnesota. “While fiber and sugar content have been the focus in previously proposed systems, and they’re important pieces of the puzzle, there needs to be more nuance in our recommendations given the breadth of foods and food groups that fall into the carb category.” Slavin is a member of the QCC-SAC, which was formed by Potatoes USA and other commodity group stakeholders that comprise the Coalition.

To provide a more complete appraisal of CF quality – and to reflect the most up-to-date dietary guidance – the new carbohydrate quality scoring system is the first of its kind to include an assessment of sodium, potassium and whole grain content in addition to sugar and fiber. These three components were added because CFs are predominant dietary sources of these nutrients. Sodium, like sugar, is consumed at levels above those recommended in current dietary guidance, and potassium and whole grains, like dietary fiber, are consumed at levels well below those recommended. By including all these components, this approach not only aligns with the recommendations of the 2020-2025 Dietary Guidelines for Americans (DGA), but also the World Health Organization, and roughly half of the food-based dietary guidelines from around the world.

“Other systems to define carb quality exist, and many rely heavily on the glycemic index; however, research increasingly shows GI has far too much inter-individual variability to offer meaningful real-world utility,” noted QCC-SAC member Siddhartha Angadi, PhD, University of Virginia. “A truly effective measure of carbohydrate food quality is one that is both accurate and practical. By capturing a broader set of dietary parameters with relevance to public health, the CFQS aims to offer relevant, real-world recommendations to potentially improve nutrient intake and public health.”

The new system builds upon previously validated measures of CF quality, namely ratios of carbohydrate to fiber (i.e., at least one gram of fiber for every 10 grams of carbohydrate) and carbohydrate to free sugar (i.e., less than one gram of free sugar for every 10 grams of carbohydrate). The addition of potassium, sodium and whole grains to the algorithm was further validated by demonstrating a high correlation with two other scientifically substantiated nutrient profiling systems: the Nutrient Rich Food (NRF9.3) index, an algorithm for assessing a food’s nutrient density, and Nutri-Score, a European model used to assess foods’ nutritional value.

“The high degree of agreement between the CFQS models and these other established metrics further support the efficacy of our approach,” explained Adam Drewnowski, PhD, University of Washington, a QCC-SAC member and creator of the NRF9.3 index. “We can say with great confidence that the CFQS is assessing the quality of carbohydrate foods in an accurate and meaningful way.”

The Carbohydrate Food Quality Score: How It Works

So far, two models have been developed using the new scoring system. One model, known as the CFQS-4, assigns a score of zero to four points to all carbohydrate-containing foods, which in this study were defined as solid foods with ≥ 40% energy from carbohydrate (as measured by 100g dry weight). The more advanced model, known as the CFQS-5, assigns a score of zero to five points, in which grain foods can score an extra point if their whole-grain content is ≥25%, which was selected as the cutoff value based on previous studies and current U.S. front-of-pack regulations.

In the CFQS-4 model:

• 1 point is awarded if fiber is ≥10g/100g carb portion
• 1 point if free sugar is <10g/100g carb portion
• 1 point if sodium is <600mg/100g dry weight
• 1 point if K >300mg/100g dry weight

In the CFQS-5 model for grain-based foods, one additional point is awarded for whole grain content:

• 1 additional point if whole grains ≥25g/100g dry weight

“This system is already much more comprehensive than previously published metrics, but it’s also designed to continue evolving with the science,” said Drewnowski. “As new data become available, the CFQS models can expand to reflect other measures of carbohydrate quality, such as the food’s prebiotic or polyphenol composition, degree of processing or aspects of fortification or enrichment.”

This report builds on an earlier QCC-SAC publication from July 2021, which reviewed the current state of CF quality metrics and established initial guiding principles for developing a new scoring metric for determining CF quality. The latest report advances this work by introducing a more broadly applicable Carbohydrate Food Quality Score and comparing it to other measures of nutrient density.

As a next step, the researchers are preparing a paper demonstrating how the new scoring system can be applied to a variety of eating patterns.

“We need tools that help people apply nutrition science to an array of cultural dietary traditions, socioeconomic contexts and personal needs and preferences,” added QCC-SAC member Judith Rodriguez, PhD, RD, University of North Florida. “That’s the ultimate aim of this work: to develop a metric that can be applied to build healthy dietary patterns for everyone.”

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The Quality Carbohydrate Coalition (QCC) is a multi-stakeholder engagement of commodity groups across the food industry. Guided by the work of its Scientific Advisory Council (SAC), this group aims to support a collaborative, scientific dialogue around the unique and diverse roles that carbohydrate-containing foods play in healthful eating.  The council is made up of six world-renowned experts in carbohydrate research, nutrient profiling, cultural competency and epidemiology: Adam Drewnowski, PhD; Julie Miller Jones, PhD, LN, CNS; Judith Rodriguez, PhD, RD; Joanne Slavin, PhD, RD; Siddhartha Angadi, PhD; and Yanni Papanikolaou, MPH.  Potatoes USA provides the funding to support the research being conducted by the SAC.

The article, “A New Carbohydrate Food Quality Score to Reflect Dietary Guidelines: An Expert Panel Report,” is published in Nutrients (doi: 10.3390/nu14071485). All QCC-SAC members were authors, supported by Kevin Comerford, PhD. Funding was provided by Potatoes USA.

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JOURNAL

Nutrients

DOI

10.3390/nu14071485 

ARTICLE TITLE

A New Carbohydrate Food Quality Scoring System to Reflect Dietary Guidelines: An Expert Panel Report

ARTICLE PUBLICATION DATE

28-Mar-2022

Read the Full Study Summary

No short-term, statistically significant difference between calorie-matched fries and almonds on key health metrics

Peer-Reviewed Publication

THE ALLIANCE FOR POTATO RESEARCH AND EDUCATION (APRE)

March 7, 2022 — White potatoes — especially French fries — are often described in nutrition research literature and dietary guidance statements as having associations with obesogenic diets and as increasing chronic disease risk based on observational research findings. However, there is limited evidence from randomized controlled trials (RCTs) testing cause-and-effect relationships. Now, an RCT published in the American Journal of Clinical Nutrition demonstrates that adding a 300-calorie serving of French fries to one’s typical diet every day for a month does not result in differential weight gain or other biomarker changes associated with impaired blood sugar regulation compared to adding an isocaloric daily serving of almonds, generally considered a healthy snack option.

“In our School of Public Health at Indiana University-Bloomington and in my own work, we adhere to a slogan: ‘It’s About Knowing.’ Because conjecture is good, but knowing is better,” says David Allison, PhD, the study’s principal investigator. “The way we come to know is through rigorous, randomized controlled trials. Based on our RCT findings, there is no statistically significant evidence of differential effects between consuming a typical 300-calorie serving of French fries daily and a 300-calorie serving of almonds daily when it comes to weight gain or markers of type 2 diabetes risk, at least in the short term.”

Changes in body composition (i.e., body fat mass), body weight, fasting glucose and fasting insulin levels at the end of the one-month trial were comparable across the French fry and almond intervention groups and were not clinically significant. As expected, given the difference in carbohydrate content between the French fries and almonds, acute peak blood glucose and insulin levels were higher after consuming the French fries. However, these levels were not elevated beyond a normal range, and this difference did not have an apparent impact on any other glucoregulatory biomarkers.

“Our results show two food items identified previously for opposite associations with health outcomes had no differences in effects on the health outcomes we measured,” notes study co-author Daniel Smith, PhD. “Nutrition recommendations that focus primarily on single foods in isolation may be missing the mark. A more effective approach to dietary guidance is likely one that takes total diet, lifestyle and individual needs and risk factors into account.”

Study Design, Strengths, and Limitations

A group of 180 adult men and women were randomized to one of three treatment groups for 30 days, with 165 completing the study. The three arms included an additional 300 kilocalories/day from one of the three food items (below) and participants were asked to add the specific food item into their “normal daily diet.”

• Almonds: approximately 1/3 of a cup of almonds, roasted and salted
• Standard French fries: approximately the size of a medium serving
• French fries with herb/spice mix: approximately the size of a medium serving, prepared with oregano, basil, garlic, onion and rosemary

Instructions were provided regarding storage and preparation methods of food items for all participants. Participants were simply asked to incorporate the specific food item into their normal daily diet. They were not instructed to compensate for these added calories in any way.

Body composition (body fat mass), body weight, blood sugar, insulin and hemoglobin A1c were measured at baseline and at study completion. A subset of five participants also completed post-meal evaluations to assess short-term blood sugar response.

The study’s strengths include its randomized controlled trial design, considered the gold standard in identifying causal relationships, as well as the standardization of the study foods’ preparation, presentation and convenience. Its limitations include the fact that it was a free-living study, limiting researchers’ control over the participants’ diets; however, such a study design also allows for real-world data collection. It also excluded participants with type 2 diabetes, limiting the application of the findings to individuals without the disease. Additionally, the study did not include an analysis of energy (calorie) intake, nor were satiety data collected, making it unclear exactly how the varied snack intakes affected calorie intake overall.

The research article, “French-fried potatoes consumption and energy balance: a randomized controlled trial,” is published in The American Journal of Clinical Nutrition (https://doi.org/10.1093/ajcn/nqac045). Authors include David Allison, PhD, Indiana University and Daniel Smith, PhD, University of Alabama at Birmingham. Funding was provided by the Alliance for Potato Research and Education; however, APRE had no influence on the study design, conduct, execution or data analysis after approving the initial proposal for funding.

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JOURNAL

American Journal of Clinical Nutrition

DOI

10.1093/ajcn/nqac045 

METHOD OF RESEARCH

Randomized controlled/clinical trial

SUBJECT OF RESEARCH

People

ARTICLE TITLE

French-fried potatoes consumption and energy balance: a randomized controlled trial

ARTICLE PUBLICATION DATE

18-Feb-2022

Read the Full Study Summary

Eating potatoes also linked to improved nutrient intakes in ‘tween’ girls

Peer-reviewed Publication

THE ALLIANCE FOR POTATO RESEARCH AND EDUCATION (APRE)

NEWS RELEASE 27-OCT-2021

Adolescence is a critical period for the evolution of cardiometabolic risk factors that are largely influenced by diet and lifestyle. Understanding these risk factors is essential to developing effective dietary guidance for disease prevention targeting this critical age period. Recently published research in the British Journal of Nutrition found that 9-17 year-old girls who consumed up to one cup of potatoes daily had no increased risk of becoming overweight or developing high blood pressure, dyslipidemia, or impaired fasting glucose by the end of the study in late adolescence.

According to the 2020-2025 Dietary Guidelines for Americans, girls aged 9 – 18 are encouraged to consume 1½ to 3-cup equivalents per day of vegetables, depending on their calorie needs, but most fail to meet these guidelines. In this study, the highest levels of potato consumption ranged from 1/5 to 1 cup per day and at that level, no adverse effects were observed.

“Our results show that nutrient-rich potatoes can be part of a healthy diet in young girls during this important period of growth and development,” says Lynn L. Moore, DSc, MPH, Boston University, the study’s senior author. “There is growing evidence that overall diet quality is what really matters in the preservation of heart health. Potatoes are an affordable food, with a number of valuable nutrients, and our research suggests that moderate intakes of potatoes, along with many other types of vegetables,  can be a regular part of a healthy diet pattern.”

Higher intakes of all forms of potatoes (including fried) during the ‘tween’ years of nine to 11 were associated with higher intakes of potassium and dietary fiber, two nutrients of public health concern, ^[i]   as well as vitamin C, vitamin B6 and magnesium. Black girls in this study with the highest intakes of potatoes also consumed more fruit and non-starchy vegetables and had higher diet-quality scores.

Study Design, Strengths and Limitations

The researchers analyzed data from nearly 2,000 subjects (approximately 50% Black, 50% White) from the National Growth and Health Study, a longitudinal study of the development of obesity and other cardiovascular-related outcomes in adolescent girls.

• For girls at 9-11 years of age, researchers analyzed data on total potato intake (white and sweet) as well as separate intakes of fried and non-fried potatoes.
• For girls at 9-17 years of age, researchers analyzed data for total potato intake (white and sweet).

Diet was assessed using 3-day diet records at baseline when girls were 9-10 years old, and during the follow-up years 2-5, 7, 8, and 10. The intake of potatoes (both white and sweet potatoes) was extracted from total vegetable servings. Anthropometric measures of body fat and body composition and blood pressure were measured annually. Additionally, fasting triglycerides, other lipids, and glucose were measured in later adolescence (at 18-20 years of age)

Repeated measures of a number of potential confounding variables were examined, including socioeconomic status, body mass index (BMI), changes in height, physical activity, television viewing, intakes of food groups and nutrients, as well as diet quality measured by the Healthy Eating Index (HEI)-2015. The study’s strengths include its prospective design as well as the use of multiple sets of three-day diet records, which is considered the gold standard method for dietary assessment. Researchers also took repeated measures of cardiometabolic risk factors and most potential confounders.

The investigators acknowledge limitations to the study, such as reliance on self-reported dietary intakes from adolescents who may have had difficulty accurately estimating portion sizes and reporting details. However, parents and other caregivers were actively involved in the completion of these diet records, especially during the earlier years of the study. Researchers were unable to assess the effects of very high levels of potato intakes since few girls reported consuming more than one cup equivalent of potatoes per day. They were also unable to analyze any differences between white and sweet potato consumption, given the low intakes of sweet potatoes within the study population. Finally, the researchers were unable to control for baseline values of fasting glucose or triglycerides due to missing or unreliable data at the initial exam.

This study was selected as the Nutrition Society’s Paper of the Month. Every month, the Editors-in-Chief of the Nutrition Society’s journals select one paper as being of particular interest or originality, and/or because it challenges previously conceived notions in nutritional science and public health. The research manuscript, “Potato consumption is not associated with elevated cardiometabolic risk in adolescent girls,” is published in the British Journal of Nutrition (https://doi.org/10.1017/S0007114521003445). Authors include Ioanna Yiannakou, Mengjie Yuan, R. Taylor Pickering, Martha R. Singer, and Lynn L. Moore, Boston University. In addition to funding from the National Institutes of Health, funding was provided by the Alliance for Potato Research and Education (APRE); APRE had no input on interpretation of the results or manuscript development.

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[i] U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2020-2025. 9th Edition. December 2020. Available online: https://DietaryGuidelines.gov

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JOURNAL

British Journal Of Nutrition

DOI

10.1017/S0007114521003445 

ARTICLE TITLE

Potato consumption is not associated with elevated cardiometabolic risk in adolescent girls

ARTICLE PUBLICATION DATE

6-Sep-2021

Read the Full Study Summary

Experts propose a nuanced approach to define high-quality carbohydrate foods while avoiding unreliable indicators, like GI

Peer-Reviewed Publication

THE ALLIANCE FOR POTATO RESEARCH AND EDUCATION (APRE)

NEWS RELEASE 16-AUG-2021

For decades, people have often associated higher intakes of carbohydrate-containing foods with less healthy lifestyles. Yet, evidence suggests this perspective view is overly simplistic, and it is instead the type and quality of carbohydrate foods (CF) that matter most for supporting health. While some measures of carbohydrate quality exist, such methods often use highly variable – and thus unreliable – indicators. In a newly published perspective in Nutrients, a group of nutrition researchers, who collectively make up the Quality Carbohydrate Coalition-Scientific Advisory Council (QCC-SAC), outline the opportunity for a stronger, more evidence-based approach to defining quality CF to support overall health and provide clearer dietary guidance.

“To better guide food choices and nutrition literacy, the dialogue around high-quality carbohydrate foods must be advanced to consider the evolving science,” explains Adam Drewnowski, PhD, University of Washington, a QCC-SAC member. “As a first step, we conducted a scoping review of the scientific literature to examine the evidence behind existing measures of carbohydrate food quality and ways in which to build upon this work.”

The QCC-SAC is a team of six world-renowned experts in carbohydrate research, nutrient profiling, cultural competency and epidemiology. The group was assembled by the Quality Carbohydrate Coalition, which was spearheaded and is funded by Potatoes USA. The Coalition’s ambition is to assess and advance evidence to explore the role of CF in health. Collectively, the QCC-SAC members agree that, based on the evidence, carbohydrate guidance must move away from individual and unique biological interactions with foods, and towards recommendations based on intrinsic qualities of a food (i.e., nutrient- and food-based indicators). This includes shifting away from the decades-old focus on glycemic index (GI) when discussing high- versus low-quality CF.

QCC-SAC consensus: GI is a flawed (and misused) approach to defining CF quality

“GI is frequently used as a metric for carbohydrate food quality – but it is an outdated and flawed indicator with too much variability,” says Julie Miller Jones, PhD, LN, CNS, St. Catherine University (Emeritus), a member of the QCC-SAC. “In fact, GI was created as a research tool for use in the laboratory and was never intended to be used by the general population. Instead, we require a measure that reflects both a carbohydrate food’s contributions to fiber, nutrient and phytochemical intake, as well as its role in a healthy diet. An omnibus measure of carbohydrate food quality indicators that is accurate and applicable to real-life eating patterns is needed.”

Specifically, research demonstrates that GI varies considerably based on different contexts, such as eating situations (e.g., mixed meals), and based on individual characteristics (e.g., biological and behavioral factors like age, weight, physical activity and gut microbiome).

“A new review analyzing GI values found the variability with rice can fluctuate so significantly that it can be considered both a low GI and high GI food,” shares QCC-SAC member Siddhartha Angadi, PhD, University of Virginia. “Further, even the GI of bread can vary up to five-fold between individuals. These large inter-individual variations make the utilization of GI as a marker of carbohydrate food quality problematic.”

Despite its historic use to guide CF choices among consumers with type 2 diabetes, GI is not a consistent predicator of health. A 2019 series of systematic reviews and meta-analyses rated the evidence regarding the long-term effects of GI on health outcomes, such as cardiovascular disease, type 2 diabetes and colorectal and breast cancer, as “low or very low.”

“These findings support the need for a new, holistic approach to replace the overreliance on GI as a single evaluator of carbohydrate quality,” states Yanni Papanikolaou, MPH, Nutritional Strategies, Inc., a QCC-SAC member.

A new, inclusive approach to defining high-quality CF

The QCC-SAC will develop a series of papers for peer-reviewed publication that will introduce a new, validated approach for measuring CF quality, and will demonstrate how the approach can be integrated into dietary guidance tools to help people of all ages, ethnicities and cultural preferences improve their food choices. The approach will involve developing a composite measure that harmonizes multiple intrinsic CF quality indicators from the scientific literature into an easy-to-use tool.

“Compared to existing metrics, this tool will be unique, evidence-based and practical,” notes QCC-SAC member Judith Rodriguez, PhD, RD, University of North Florida. “It will reflect how people actually eat (e.g., mixed meals) and will recognize cultural patterns and traditions – a novel approach that is often underrepresented in similar dietary guidance tools.”

The QCC-SAC plans to release more details on their harmonized composite approach to assess CF quality in the coming year.  

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The Quality Carbohydrate Coalition is a multi-stakeholder engagement of eight organizations across the food industry. Guided by the work of its Scientific Advisory Council, this group aims to support a collaborative, scientific dialogue around the unique and diverse roles that carbohydrate foods play in healthful eating.

The Quality Carbohydrate Coalition-Scientific Advisory Council (QCC-SAC) is a group of six world-renowned experts in carbohydrate research, nutrient profiling, cultural competency and epidemiology. The aim of the QCC-SAC is to determine evidence-based approaches for defining and selecting quality carbohydrate foods. Members of the QCC-SAC include Adam Drewnowski, PhD; Julie Miller Jones, PhD, LN, CNS; Judith Rodriguez, PhD, RD; Joanne Slavin, PhD, RD; Siddhartha Angadi, PhD; and Yanni Papanikolaou, MPH.

The report, “Toward an evidence-based definition and classification of carbohydrate quality foods: An expert panel report,” is published in Nutrients (doi: 10.3390/nu13082667). All QCC-SAC members were authors, supported by Kevin Comerford, PhD. Funding was provided by Potatoes USA.

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JOURNAL

Nutrients

DOI

10.3390/nu13082667 

ARTICLE TITLE

Toward an Evidence-Based Definition and Classification of Carbohydrate Food Quality: An Expert Panel Report

ARTICLE PUBLICATION DATE

31-Jul-2021

Read the Full Study Summary

Research suggests that, among nine- to 18-year-olds, eating potatoes can be an effective strategy to modestly improve intake of key shortfall nutrients

Peer-Reviewed Publication

THE ALLIANCE FOR POTATO RESEARCH AND EDUCATION (APRE)

NEWS RELEASE 2-AUG-2021

American youth between two and 19 years-old have the lowest measures of diet quality compared to other age groups;[1] and nutrition thought leaders have called for effective strategies to reverse this trend and improve adherence to dietary recommendations. Now, new research published in Nutrients finds U.S. adolescents who eat potatoes have higher quality diets than those who do not consume potatoes, regardless of how the potatoes are processed or prepared. Compared to no potato consumption, results showed that eating potatoes in any form (baked, boiled, mashed, in mixed dishes and fried) was associated with higher intakes of several essential nutrients, including dietary fiber and potassium – two nutrients of public health concern^[2] – and improved nutrient adequacy.

“The potato is a nutrient-dense vegetable that provides important, critically under-consumed nutrients to adolescent diets,” says Victor Fulgoni, III, PhD and study co-author. “Given their popularity—more than half (56%) of those surveyed reported eating some form of potatoes—there are opportunities to lean into these findings to make it easier for young people to find, cook and enjoy potatoes as part of a healthy dietary pattern.”

Researchers gathered dietary information from 16,633 nine- to 18-year-olds participating in the National Health and Nutrition Examination Survey (NHANES) 2001-20018. This study used Healthy Eating Index-2015 (HEI), a validated measure of diet quality, to determine how closely the participants’ diets adhered to the 2015-2020 Dietary Guidelines for Americans. Although differences in HEI scores between potato consumers and non-consumers were statistically significant, the changes were modest; for many nutrients, intake and adequacy improved with increasing potato consumption. Specifically:

• HEI scores were 4.7% higher among those who consumed potatoes that were baked/boiled, mashed or eaten as part of a mixed dish compared to those who ate no potatoes.
• HEI scores were 2% and 1.6% higher than potato non-consumers, respectively, among adolescents who ate either fried potatoes or those who ate fried potatoes and/or potato chips.

“Our findings show that potatoes play an important role with helping adolescents better meet the recommendations set forth in the Dietary Guidelines for Americans,” notes Fulgoni. “This is an important goal as, according to the USDA Agricultural Research Service, children and adolescents have the lowest HEI scores among any age group in the U.S. – just 53 out of an ideal HEI score of 100.”

“Our results also bring attention to the ‘company potatoes keep,’” Fulgoni adds. “Fried potatoes and potato chips are often paired with less nutrient-dense foods, which can’t be teased out in this type of study but may explain the slightly lower diet quality scores among these groups of potato eaters compared to baked/boiled potato eaters. Additional clinical trials are needed to better elucidate this situation.”

Study Design, Strengths and Limitations

Nutrition intake was determined by using two 24-hour dietary recalls. The first was conducted in person; the second was performed over the phone. Adolescents aged nine to 11 were assisted by parents or guardians, while those aged 12-18 provided recalls on their own. Based on their responses, participants were classified into one of four groups:

• Potato non-consumers
• Consumers of baked, boiled, mashed potatoes and potato mixtures
• Consumers of baked, boiled, mashed potatoes and potato mixtures + fried potatoes
• Consumers of baked, boiled, of baked, boiled, mashed potatoes and potato mixtures + fried potatoes + potato chips

Usual intake of nutrients was determined using the National Cancer Institute method, and diet quality was calculated using HEI-2015 scores after adjusting for demographic factors. The HEI-2015 includes 13 subcomponents, each reflecting an aspect of the 2015-2020 Dietary Guidelines for Americans.

The strengths of the study include its use of a large nationally representative database (NHANES 2001-2018) and the use of multiple covariates to help eliminate potential confounding factors. However, the researchers also acknowledge a few limitations namely, the cross-sectional study design cannot be used to determine causal relationships, and dietary recalls may be subject to inaccurate reporting. Additionally, even with the use of covariates, residual confounding may exist.

The research manuscript, “Intake of potatoes is associated with higher diet quality, and improved nutrient intake and adequacy among US adolescents: NHANES 2001-2018 analysis,” is published in Nutrients (https://doi.org/10.3390/nu13082614). Authors include Sanjiv Agarwal, PhD, NutriScience, LLC and Victor L. Fulgoni, III, PhD, Nutrition Impact, LLC. Funding was provided by the Alliance for Potato Research and Education, however APRE had no input on interpretation of the results or in drafting the manuscript.

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[1] National Center for Health Statistics, What We Eat in America/National Health and Nutrition Examination Survey, 2015-2016. Healthy Eating Index-2015 Scores—U.S. Department of Agriculture, Center for Nutrition Policy and Promotion, access https://www.fns.usda.gov/resource/healthy-eating-index-hei

[2] U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2020-2025. 9th Edition. December 2020. Available online: https://DietaryGuidelines.gov

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JOURNAL

Nutrients

DOI

10.3390/nu13082614 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Intake of Potatoes Is Associated with Higher Diet Quality, and Improved Nutrient Intake and Adequacy among US Adolescents: NHANES 2001–2018 Analysis

ARTICLE PUBLICATION DATE

29-Jul-2021

Read the Full Study Summary

A more complex, holistic and non-reductionist approach to defining carbohydrate quality is needed

Peer-Reviewed Publication

FOODMINDS LLC

NEWS RELEASE 21-JUL-2021

Carbohydrates have traditionally been the largest source of energy intake for much of the world’s population¹. However, without a standard definition for carbohydrate quality, some foods that contain carbohydrates are often stigmatized based on isolated and reductionist assessment methods that fail to consider their contributions to nutrient intakes and balanced, healthy diets. A new perspective piece, published in Advances in Nutrition, brings to light the pressing need to define carbohydrate quality, to better assess the value of nutrient-dense carbohydrate-containing foods in healthy lifestyles. Ultimately, the authors call for a more holistic approach to carbohydrate guidance to address the complex needs of both people and the planet.

“To date, terms like ‘good carbs’ and ‘bad carbs’ have been inconsistently assigned to a plethora of foods based on overly simplistic and narrowly focused measures, like glycemic index (GI) or fiber content,” states Rebekah Schulz of University of Minnesota and perspective piece coauthor. “While these aspects can be individual pieces of the puzzle, they don’t reflect the full picture of carbohydrate quality. For example, while GI may be a useful index in isolation, it is not representative of real-life dietary intake when carbohydrates are consumed with other foods, nor does it account for a food’s overall nutrient content or planetary impact.”

This paper addresses the strengths and weaknesses of current methods used to assess carbohydrate quality, proposes additional indices to include in a standardized quality carbohydrate definition, and defines research questions for further exploration. Within the perspective piece, authors analyzed various existing frameworks for carbohydrate quality and weighed the pros and cons of indexing based solely on measures such as GI, whole grain foods, fiber and added sugar.

The authors concluded that, “for truly relevant and applicable dietary guidance, the framework should focus on nutrient contributions and take into account various ways to measure and analyze nutrients, as well as be nimble to adjust for new research findings and data.”

Carbohydrate Quality: Spotlight on Fruits & Vegetables

The authors also note that current approaches to assessing carbohydrate quality may lead to even greater consumer confusion of nutritional recommendations for specific foods, including fruits and vegetables. Given that one in 10 Americans fall short of meeting their fruit and vegetable requirements², it’s important that a holistic and standardized approach to dietary carbohydrate guidance is established to promote both human and planetary health as effectively as possible.

“Potatoes are one example of a food that tends to be misclassified or misunderstood based significantly on their GI value – even though preparation techniques and common consumption methods are not reflected accurately within a GI value,” points out Joanne Slavin, PhD, RD of University of Minnesota and perspective piece coauthor. “Potatoes are a nutrient-dense vegetable that provide several important nutrients – like fiber, potassium, Vitamin C and resistant starch – to Americans’ diets and have been consumed for centuries as a main staple in various cultures. Additionally, potatoes serve an important role in food security in developing countries.”

A Forward-Looking Solution: Establishing a Standardized Carbohydrate Quality Metric

Overall, there is a general shift away from one-directional and overly simplified dietary guidance, as any food or nutrient can have a place as part of a healthy lifestyle. Thus, to best define high quality carbohydrates, the authors call for a standardized carbohydrate quality metric, such as an algorithm that encompasses a broader spectrum of factors.

“There is a need to provide easy tools grounded in strong science,” added Schulz. “When consumers need to make a quick choice about carbohydrate-containing foods, they should feel comfortable knowing that there is a comprehensive, science-backed formula or algorithm behind-the-scenes helping guide this decision.”

The authors propose several potential quality indices to be considered when assessing carbohydrate quality:

• Whole-grain, fiber, and added-sugar content
• Ratios of total carbohydrate to fiber and added sugar to fiber in a food
• Protein quality
• Degree of processing
• Environmental impact of a food

“As dietary guidance rightly moves away from isolated nutrient recommendations toward broader and more flexible dietary patterns, it’s clear we need to better define the quality underpinnings of these patterns, including carbohydrates,” notes Slavin. “By establishing an algorithm to assess carbohydrate quality, the result would positively impact both health and environmental outcomes and create consistent ways to measure intake across populations.”

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The perspective piece, “Perspective: Defining Carbohydrate Quality for Human Health and Environmental Sustainability,” is published in Advances in Nutrition (https://doi.org/10.1093/advances/nmab050). Authors include Rebekah Schulz and Joanne Slavin, PhD, RD, University of Minnesota. The authors reported no funding received for this work. Joanne Slavin has received prior funding from Potatoes USA.

Footnotes

1 FAO. FAOSTAT. Available from: http://www.fao.org/faostat/en/#data/QC

2 Lee-Kwan SH, Moore LV, Blanck HM, Harris DM, Galuska D. Disparities in State-Specific Adult Fruit and Vegetable Consumption — United States, 2015. MMWR Morb Mortal Wkly Rep 2017;66:1241-1247. DOI: http://dx.doi.org/10.15585/mmwr.mm6645a1 external icon

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JOURNAL

Advances in Nutrition

DOI

10.1093/advances/nmab050 

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New study findings show that people with type 2 diabetes can better maintain overnight glycemic control when high Glycemic Index (GI) potatoes are included in an evening meal versus low GI basmati rice

Peer-Reviewed Publication

FOODMINDS LLC

People with type 2 Diabetes (T2D) are frequently told to avoid eating potatoes, and other high Glycemic Index (GI) foods, because of the longstanding perception that these foods make it difficult to control blood sugar levels. This is especially problematic during the night when blood sugar tends to spike — a phenomenon that has been associated with cardiovascular disease and endothelial disfunction. However, for the first time, a rigorously controlled clinical trial, including 24 adults with T2D, demonstrates that GI is not an accurate surrogate for an individual’s glycemic response (GR) to a food consumed as part of an evening meal. Specifically, the findings published in Clinical Nutrition show that participants had a better ‘nocturnal’ GR when they ate a mixed meal with skinless white potatoes compared to an isoenergetic and macronutrient-matched mixed meal that included a low GI carbohydrate food — basmati rice.

“Despite its frequent use among nutrition researchers, GI is not an appropriate tool for understanding how a meal impacts glycemic control; it is a very specific measurement for foods consumed in isolation, typically conducted under controlled laboratory conditions,” says Dr. Brooke Devlin, PhD, the primary investigator, at Australian Catholic University in Melbourne. “It’s rare that people eat foods in isolation, and findings from this study demonstrate how other factors, such as the time of day or food pairings, need to be considered when investigating the GR of mixed meals in individuals with T2D.”

Participants were provided the same breakfast and lunch, but they were randomly assigned to one of four dinners, each including either skinless white potatoes (test meal) prepared in three different ways (boiled, roasted, boiled then cooled then reheated) or basmati rice (control meal). Participants repeated the experiment, with a 9-day break in between each trial, to cycle through all test meals and the control. In addition to having blood samples collected regularly (both immediately after the meal and again every 30 minutes, for 2 hours), participants also wore a continuous glucose monitor overnight to track changes in blood sugar levels while sleeping.

There were no differences between meals in glucose response following the dinner that contained any of the potato dishes or basmati rice. Moreover, participants’ overnight GR was more favorable after eating the evening meal that included any of the high GI potato side dishes compared to low GI basmati rice.

“These findings are contrary to that of observational research and traditional dietary guidance that has led some to believe potatoes are not an appropriate food choice for people with T2D,” added Devlin. “Our study shows high GI foods, like potatoes, can be consumed as part of a healthy evening meal without negatively affecting GR — and while delivering key nutrients in relatively few calories, which is essential for people with T2D.”

This study followed a rigorous methodology by using a randomized crossover design and measuring glucose levels both immediately post-meal and overnight to obtain a better picture of the potatoes’ impact on GR. However, the researchers noted a few limitations: study participants’ baseline GR was assessed for only one evening meal, the dinner provided was larger than what is typically recommended for people with T2D (but in line with Australian eating patterns, at 40 percent of an individual’s total energy intake), and the potatoes’ impact on long-term glycemic control was not assessed.

Despite such limitations, the researchers concluded that “potatoes are a vegetable that is sustainable, affordable and nutrient-dense, and thus, they can play an important role in modern diets irrespective of metabolic health status.”

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The article, “Lower nocturnal blood glucose response to a potato-based mixed evening meal compared to rice in individuals with type 2 diabetes,” is published in Clinical Nutrition (doi: https://doi.org/10.1016/j.clnu.2020.09.049.) Authors include Brooke L. Devlin, Evelyn B. Parr, Bridget E. Radford, and John A. Hawley of Australian Catholic University. Funding was provided by the Alliance for Potato Research and Education.

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JOURNAL

Clinical Nutrition

DOI

10.1016/j.clnu.2020.09.049 

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White potatoes are as effective as commercial sports products in exercise fueling, performance and recovery, according to research funded by the Alliance for Potato Research & Education

NEWS PROVIDED BY

The Alliance for Potato Research & Education 

Oct 15, 2020, 08:36 ET

CHICAGO, Oct. 15, 2020 /PRNewswire/ — Lab-manufactured sports products are a go-to supplement for many athletes today to maximize performance. But as consumers seek out simpler foods, there is an opportunity to find more diverse, whole food options for athletes. A series of recent studies published in Nutrients, Journal of Applied Physiology and European Journal of Applied Physiology, shows promising results for one whole food option – the potato. These three studies demonstrate that whether consumed before, during or after workouts, potatoes positively impact performance and recovery as effectively – and sometimes more effectively than – traditional commercial sports products, such carbohydrate gels.

Nicholas Burd, PhD, primary investigator of the study published in the Journal of Applied Physiology explained, “While ingestion of concentrated carbohydrate gels is commonplace, my study indicates that whole food alternatives – like potatoes – when fed during exercise, are equally effective in supporting athletes’ performance. These promising results complement two studies from my peers, demonstrating that potatoes can also support muscle building and recovery. Collectively, these are important findings as they provide a new wholesome, nutrient-dense and cost-effective option for athletes.”

Together, these studies are a foundational turning point for both the sports and nutrition research world – opening up new fueling and recovery sources for active people and novel research hypotheses for scientists. Specifically, the studies found that:

• As a significant part of a higher protein diet (above the Recommended Dietary Allowance, or RDA), consuming potato protein isolate throughout the day for two weeks – including before resistance exercise – increased muscle protein synthesis in women (Oikawa et al., Nutrients, 2020)
• Russet potatoes consumed during a cycling trial improved performance and sustained blood glucose concentrations of trained athletes equal to that of a commercial sports gel (Burd et al., J App Physiol, 2019)
• Potato-based products consumed after a 90-minute cycling trial helped replenish muscle glycogen stores and support subsequent exercise as effectively as common sports supplements (Flynn et al., Eur J App Physiol, 2020)

According to Brent Ruby, PhD, FACSM, the lead researcher of the study published in the European Journal of Applied Physiology, finding effective and agreeable foods to fuel exercise is important, and potatoes can fit this bill. “Evidence shows many athletes – especially women – have lower energy intakes and consume less than the recommended amount of daily carbohydrates during intensive segments of training and competitions. In our study, there were no differences in post-exercise muscle glycogen recovery and time trial performance when we compared common sport supplements with a potato-based feeding plan. Moreover, participants rated the post-exercise potato meals as more tasty, satisfying and acceptable compared to commercial sports supplement foods. This indicates that potatoes may be a viable and more economical option to help athletes meet their recovery fueling needs,” explained Dr. Ruby.

Stuart Phillips, PhD, lead researcher for the study published in Nutrients, further added that his research is important for consumers leaning towards plant-based lifestyles. According to Dr. Phillips, “Plant-based diets are certainly growing in popularity. But compared to animal-derived proteins, we know much less about how plant-based proteins can support muscle protein synthesis. Our study demonstrates that potato protein – which is a high-quality protein comparable to animal-based sources and better than many plant sources – is an effective option for exercise regimens and muscle protein synthesis.”

While choosing potatoes as an optimal performance food may seem odd and difficult to execute, the trials demonstrate that various potato forms can be used to support athlete’s needs – ranging from a simple puree to potato pancakes or hash browns. According to Dr. Burd, “Potatoes are a versatile ingredient and there are many different forms of this vegetable for consumers today. While we tested a potato puree in our study, athletes can opt for different potato recipes and on-the-go products as their exercise fuel.”

These three studies provide exciting new evidence to the field of sports nutrition, but they are just a start. According to Dr. Phillips, “Our study is the first, to our knowledge, to examine effects of potato protein supplementation in any capacity in humans – and it clearly showed the inadequacy of the protein RDA. Given that recommendations and personal preferences are shifting to more plant-based, whole food options, we need more research around diverse fuels for athletes and active people alike. Researchers should continue this important work and consider other ways in which potato-derived ingredients, in various forms and situations, can support exercise performance.”

All three studies were funded by the Alliance for Potato Research and Education (APRE). APRE is a not-for-profit organization funded by the potato industry, including potato growers and processors, dedicated to advancing the scientific understanding of the role potatoes play in nutrition and health. Learn more at www.apre.org. 

Media Contact:

Laurie Hainley

202-878-8309

256750@email4pr.com

SOURCE The Alliance for Potato Research & Education

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Peer-Reviewed Publication

MCMASTER UNIVERSITY

Researchers from McMaster University have found that the potato, primarily known as a starchy vegetable, can be a source of high-quality protein that helps to maintain muscle.

The findings, reported in the journal Nutrients, highlight the potential benefits of what is considered a non-traditional source of protein, particularly as dietary trends change and worldwide demand has increased for plant-based alternatives to animal-derived sources.

“While the amount of protein found in a potato is small, we grow lots of potatoes and the protein, when isolated, it can provide some measurable benefits,” says Sara Oikawa, a former graduate student in the Department of Kinesiology at McMaster and lead author of the research paper.

The researchers recruited young women in their early twenties who consumed diets containing protein at the recommended dietary allowance (RDA) of 0.8 grams of protein/ per kilogram of weight/day, which would be approximately 60g of protein for the average woman or 70g for the average man.

One group of participants consumed additional potato protein isolate – in the form of a pudding–doubling their intake of the RDA to 1.6g/kg/d. Another group received a placebo.

Researchers found the women who consumed the additional potato protein increased the rate at which their muscles made new protein, while the placebo group did not.

“This was an interesting finding that we did not expect,” says Oikawa. “But it is one that shows the recommended daily allowance is inadequate to support maintenance of muscle in these young women.”

Perhaps more interesting, she says, was that a form of plant-derived protein, which has generally been thought to be of lower quality than animal-derived protein, can have such a beneficial effect.

To study the impact of weightlifting, the research team then instructed both groups of women to exercise only one of their legs.

“This method is a little unconventional but allows us to see the effect within the same person and not have to add more people who were exercising,” said the study principal investigator Stuart Phillips, who is a professor in the Department of Kinesiology at McMaster and a leading researcher on protein and exercise.

In the leg the women exercised, scientists did not find any extra benefits from potato protein.

“That finding, which some may find disappointing, is in line with the rather small effect that protein has compared to exercise itself,” explains Phillips. “In other words, exercise is just such a more potent stimulus for making new muscle proteins compared to protein.”

The demand for protein has risen dramatically to meet the increased demands from the rising global population and plant-based proteins could fill that gap.

“This study provides evidence that the quality of proteins from plants can support muscle,” says Oikawa. “I think you’ll see more work on plant-based protein sources being done.”

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The research was funded by the Alliance for Potato Research & Education.

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JOURNAL

Nutrients

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